Newton's Laws Objective In this lesson, you will Types of Forces A force is simply a push or pull exerted on an object. A force can change the speed or direction of of an object. Because force has both magnitude and direction, it is a I quantity. In the International System of Units (SI), the unit for measuring the magnitude of force is (N). Forces are of two types: forces and or fundamental, forces. As the name suggests, contact forces are forces that exist between objects whose surfaces each other. Contact forces occur because the on the surfaces of objects touching each other interact. Types of contact forces are tension, normal force, and An example of tension is a block